Description an exploration into the different ways you can. You cannot define the same cursor more than stead you can only use it. I need some inputs on since procedures returns control back when both these cursors sqls gets executed holding around 70,000 records. Oracle 11g identifies a different categorization basis of implicit cursors. When a ref cursor is defined with a return type, it is called as a strongly typed static ref cursor. This is the easiest way to use sql in your program. When using the data provider to work with oracle ref cursors, you should consider the following behaviors. Returning a jdbc result set from an oracle stored procedure. To use cursor variables, you must define a ref cursor type. It not only avoids the exception threat but also well indents the coding standards.
Simple grid report example using basic oracle stored. Last issue, i wrote about some new oracle database 11g features, and i continue that coverage in this issue, focusing on my favorite procedural language, plsql. The following example shows you how to get a list from an sql select query which is located in a string and dynamically openend into a ref cursor. A ref cursor is an oracle plsql data type that represents a pointer to a result set in the oracle database. Explicit cursors are best suited in situations where number of records in the result set is not known. Strong types are tied to a specific set of a tables columns. For example, you can declare a cursor variable in a plsql host environment such as an oci or proc program, then pass it as an input host variable bind variable to plsql. Cursor can be attached to only one query while ref cursor can be used to associate multiple queries at run time. Net managed provider for oracle to pass an input parameter to retrieve a ref cursor from an oracle stored procedure donwload oracle data access components. I hope before knowing about ref cursors you would have a fair idea of what cursors in general are. Plsql variables, attributes, and executable statements.
The only way i can think of doing it would be to load all the data from the cursors into a collection, or plsql table, and then use that collection as the datasource for the ref cursor. Oracle magazine subscriptions and oracle white papers. Stack overflow for teams is a private, secure spot for you and your coworkers to find and share information. Returning multiple ref cursors from oracle using daab. Strong plsql ref cursors burleson oracle consulting. Run operations using ref cursors in oracle database using. In stateful applications this could be used to page through results. Visual basic with oracle 11g using ref cursor not working. Using plsql stored procedures and ref cursors oracle.
Cursor variables give you easy access to centralized data retrieval. Example 711 procedure vulnerable to sql injection through data type. Building a paper report with ref cursors oracle docs. Say the business requirement changes so that the data should be displayed in a different order. Create the following oracle package body on the oracle. Fusion middleware oracle reports users guide to building reports. Working with exceptions, subprograms, jdeveloper, and ref cursors. Our technologist takes another look at oracle database 11g.
Simple grid report example using basic oracle stored procedure in japser design studio 6. Strong ref cursor and weak ref cursor for the strong ref cursor the returning columns with datatype and length need to be known at compile time. Plsql ref cursor and oraclerefcursor oracle help center. This example demonstrates how to define and open a ref cursor variable, and then pass it as a procedure parameter. It is a better alternative to working with in memory oracle tables. Declares a ref cursor and passes it on to the plsql stored procedure along with the above generated department number deptno. Application development tools such as oracle forms, which have a plsql engine, can use cursor variables entirely on the client side. This means a strong ref cursor type can only be used. Demos, syntax, and example code of oracle plsql strongly typed and weakly typed ref cursors. How to use a ref cursor to pass a varray and disassemble it on the receiving end. With ref cursors, no need to load the whole result set into a table variable, and have the. Meaning that a cursor variable can be opened for any query.
In this example, we declared a parameterized cursor with default values. Area plsql general plsql procedures, functions, packages. Oracle plsql ref cursors ref cursors a ref cursor or cursor variable is just a reference or a handle to a static cursor. I am using several package functions to return ref cursors to a java front end. Part 12 in a series of articles on understanding and using plsql. Normal cursor is a static cursor in which the query is assigned at design time and cant be changed at run time. Showing equipment records by using a ref cursor oracle docs. A variable created based on such a data type is generally called a cursor variable.
Oracle 11g performance tuning oce oracle 11g r2 rac oce. Plsql cursor variables with ref cursor oracle tutorial. To read more about ref cursor i have created a package to explain few different ref cursor examples. Introduction to oracle 11g cursors eye on databases. In essence, a ref cursor is a pointer or a handle to a result set on the database. The advantage that a ref cursor has over a plain cursor is that is can be passed as a variable to a procedure or a function. Ref cursor declaration is not associated with any sql query different queries can be associated with the cursor programatically. Two out ref cursors fetches around 70,000 records and for each record again some internal procedures gets called we have done some changes to queries used to fetch these ref cursors data. It allows a user to pass this reference to the same cursor among all the programs that need access to the cursor. Now, you should know how to use a plsql cursor with parameters to fetch data from the database tables. Call oracle stored procedure which returns ref cursor in. Alternative to cursors performance oracle community. What is the difference between a normal cursor and a ref. I think you should read the title of project and sufficient knowledge about topic before write any comment on that.
This article is about the use of multiple ref cursors from oracle using daabenterprise library not how you use multiple ref cursors in your code. Ian abramson, michael abbey, michelle malcher, michael corey. Ask tom refcursors vs pipelined functions 11g oracle. This article demonstrates a few simple ways to display the contents of ref cursors. A ref cursor that specifies a specific return type. Net type for the ref cursor type this section discusses the following aspects of using the ref cursor data type and oraclerefcursor objects obtaining an oraclerefcursor object. As other answers pointed out they are memory structures used to temporarily store and iterate through a query result set in plsql. Visit plsql challenge to read a complete explanation of the answers to this quiz.
Different types of cursors in plsql oracle live sql. Well everything works fine, the test team just send me an example with a ref cursor which looks simple comparing to a for loop. Strong plsql ref cursors oracle plsql tips by boobal ganesan. Using ref cursors is one of the most powerful, flexible, and scalable ways to return query results from an oracle database to a client application a ref cursor is a plsql data type whose value is the memory address of a query work area on the database. For the weak ref cursor the structure does not need to be known at compile time. Thus, inserting a line like the following will provide you with the capability to access data in the database. The problem is to receive the recordsets from the database. Description dml in a table function with a ref cursor as a parameter. It represents a cursor or a result set in oracle database. A cursor variable is a variable that references to a cursor. A ref cursor is a variable, defined as a cursor type, which will point to, or reference a cursor result. Using data types, index by tables, and cursors in plsql. Declare type empcurtyp is ref cursor return emp%rowtype. They also told me that cursors and sequences slow down the db performance.
Net framework data provider for oracle supports the oracle ref cursor data type. A cursor can allow more flexibility than writing a plsql function that returns an array as its completely up to the client how many rows to fetch and when to. Java,stored procedure,oracle,stored procedures and java. The ref cursor is a data type in the oracle plsql language. Resultset 5 in the query editor manually type the field names and provide types to them as shown in below image. A cursor variable can be associated with different queries at runtime. Using dml, ddl, cursors, control structures, and loops. The primary advantage of using cursor variables is their capability to pass result sets between sub programs like stored procedures, functions. Run operations using ref cursors in oracle database using the wcf service model. When we opened the cursor, we did not pass any arguments.